做视频网站需要什么服务器配置,做网站头片的高清图,创业ppt模板免费,怎么自己免费做网站使用 condition_variable::wait(unique_lockmutexlck, Predicate pred) 时#xff0c;必须保证条件变量通过notify唤醒的同时#xff0c;wait 的第二个参数 Predicate 返回 true 了才可以往下走。必须两个条件同时满足#xff0c;如果notify的时候Predicate返回… 使用 condition_variable::wait(unique_lockmutexlck, Predicate pred) 时必须保证条件变量通过notify唤醒的同时wait 的第二个参数 Predicate 返回 true 了才可以往下走。必须两个条件同时满足如果notify的时候Predicate返回时false一样的唤不醒线程。
#include iostream
#include future
#include chrono
#include string
#includefunctional
#include queueusing Task std::functionvoid();
class ThreaPool
{
public:void start() {running_ true;}bool is_running(){return running_;}void stop() {std::cout stop... std::endl;running_ false;std::unique_lockstd::mutex lk(qmutext_);tasks_.push([]() { std::cout hello pool end std::endl; });cond_.notify_all();}void push_task(Task task) {if (!running_){return;}std::unique_lockstd::mutex lk(qmutext_);tasks_.push(task);cond_.notify_one();}ThreaPool(int count){for (int i 0; i count; i){pool_.emplace_back([this]() {while (true){Task task;{std::unique_lockstd::mutex lk(qmutext_);std::cout wait 1 std::endl;cond_.wait(lk, [this] {return !running_ || !tasks_.empty(); });std::cout wait 2 std::endl;if (!tasks_.empty()){task std::move(tasks_.front());tasks_.pop();}}if (task){task();}if (!this-is_running()){std::cout stoped 1 std::endl;std::unique_lockstd::mutex lk(qmutext_);if (tasks_.empty()) {std::cout stoped 2 std::endl;return;}}}});}}~ThreaPool() {for (std::thread worker : pool_) {worker.join();}};private:std::vectorstd::thread pool_;std::mutex qmutext_;std::condition_variable cond_;std::queue Task tasks_;std::atomic_bool running_{ true };
};int main()
{ThreaPool pool(5);std::this_thread::sleep_for(std::chrono::seconds(1));pool.push_task([]() { std::cout hello pool 1 \n std::endl; });pool.push_task([]() { std::cout hello pool 2 \n std::endl; });pool.push_task([]() { std::cout hello pool 3 \n std::endl; });pool.push_task([]() { std::cout hello pool 4 \n std::endl; });pool.push_task([]() { std::cout hello pool 5 \n std::endl; });pool.push_task([]() { std::cout hello pool 6 \n std::endl; });pool.push_task([]() { std::cout hello pool 7 \n std::endl; });pool.push_task([]() { std::cout hello pool 8 \n std::endl; });pool.push_task([]() { std::cout hello pool 9 \n std::endl; });std::this_thread::sleep_for(std::chrono::seconds(1));pool.stop();return 0;
}
